Safeyt Assessment Of Rice Genetically Modiifed With CrylAc And Sck By Feeding Studies On Broilers

The feeding trial was conducted to evaluate the feeding value of transgenic brown rice modifiedwith Cry1Ac and sck gene, and study the effect of this kind of rice on,immunity, intestinal microfloraand Cry1Ac gene protein in body or stool of broilers. Its objective was to provide the experimentalsupport for feeding safety evaluation of the transgenic brown rice modified with Cry1Ac and sck gene.A42-days feeding study was used to evaluate whether a broilers diet prepared with brown rice orwith transgenic rice modified with Cry1Ac and sck gene or with corn had any unanticipated adverseeffects on broilers.360Arbor Acres broilers with one day old were randomly divided into threetreatment groups (transgenic brown rice group, parent brown rice group, corn group). The control groupwas fed with brown rice and corn, while the test group was fed transgenic brown rice. The effects oftransgenic brown rice were studied on nutritional safety, immune safety, variation in intestinalmicroflora and the residual of Cry1Ac gene protein in body and stool. The test results were as follows:1. The nutrient composition of the brown rice and transgenic riceThere was no significant difference between brown rice and transgenic rice for the nutrientcomposition such as crude fat, ash, crude fiber, moisture, crude protein, amino acid.2The effects of rice genetically modified with Cry1Ac and sck gene as feed of broilers on nutritionalsafety.There was no significant difference between transgenic brown rice modified with Cry1Ac/sck genegroup and the parental brown rice diet group or commodity corn diet group for growth performance(feed consumption, body weight gain and feed conversion ratio) of broiler chickens from1to21d, from22to42d, or from1to42d. The contents of crude protein, crude fat, crude ash, amino acids, calciumand phosphorus and other nutrients in the muscle composition among the three groups had nosignificant differences. Regard to nutrition digestion performance of broilers, there was no significantdifference between transgenic Cry1Ac/sck gene brown rice group and parental brown rice group orcommodities group for total energy, dry matter, crude protein, crude fat, crude ash, amino acids,calcium and phosphorus apparent digestibility. Carcass traits of broiler chickens: eviscerated yield,semi-eviscerated yield, breast muscle rate, leg muscle ratio and abdominal fat percentage had nosignificant differences among the three groups. There was no significant difference for the organ indexof broilers between the transfer Cry1Ac/sck gene brown rice group and parent brown rice group orcommodity corn group. Transgenic Cry1Ac/sck gene brown rice did not cause significant adverseeffects on the growth performance, digestive function, slaughter performance, or organ growth ofbroilers.3The effects of rice genetically modified with Cry1Ac and sck gene as feed of broilers on immunesafety. During the experimental period, feeding trasferring Cry1Ac/sck gene brown rice had no significantimpact on index of immune organs, blood, blood biochemistry, serum lysozyme activity, antibodiesagainst the virus titer, T-lymphoid and B-lymphocyte transformation rate, serum antioxidantcapacityindex, biopsy of various organs and tissues, or the intestinal lymphatic slice of broilers. Serum hormoneand TLR5indexs belonging to immune factor indicators between the transgenic group and parent grouphad significant differences, while there was no significant difference for other indicators. There werestatistical differences for these two indicators, but no biological differences. Based on above, it can beobtained that, during the trial period, turn Cry1Ac/sck gene brown rice as the the broilers raw materialhad no significant impact on the immune performance of broilers. Therefore, the transgenic brown ricemodified with Cry1Ac and sck gene on the immune performance of broilers was safe.4The effects of rice genetically modified with Cry1Ac and sck gene as feed of broilers on intestinalmicroflora.Total aerobes, total anaerobes, lactobacilli, E. coli in ileum and cecum of broilers were cultured for21d and42d by conventional flat, respectively. The resluts showed total aerobic bacteria in the21dileum transgenic group was significantly higher than the parent group; Lactobacillus transgenic group in42d cecal was significantly higher than the parent group; there was no significant difference between theremaining bacteria in the transgenic group and parent group. PCR-DGGE polyacrylamide gelelectrophoresis bands of ileum and cecal intestinal microbial in broilers showed there was no significantquantity difference among these three groups. The overall similarities among the three groups were15%and55%, respectively, indicating that intestinal microbial species in broiler existed large individualdifferences among three groups. Overall, the transgenic brown rice modified with Cry1Ac and sck genehad no a significant impact on cecal microbial populations.5Residual Cry1Ac gene protein was detected in the body of broilersThe Cry1Ac protein content was detected in organs, intestine, muscle and faeces of broilers fed bytransgenic brown rice. The results showed that the Cry1Ac proteins were all not found.These results suggested that, during the experimental period, the turn Cry1Ac/sck gene brown ricedid not cause obviously negative effects on nutrition performance, immune performance, and intestinalmicroflora of broilers. The Cry1Ac protein was not found in organs, muscles, intestinal and the fecesresidues of broilers. Therefore, tansferring Cry1Ac/sck gene brown rice as broiler feed was safe.